VeraCrypt provides disk encryption with strong security based on TrueCrypt. Prior to 1.26.29, non-default builds created with WOLFCRYPT=1 and WOLFCRYPTBACKEND route SHA-256 and SHA-512 volume-header key derivation through derivekeysha256 and derivekeysha512 in src/Crypto/wolfCrypt.c, where the configured iterations value is discarded and wcHKDF is used instead of PBKDF2-HMAC. Changing the PIM or iteration count therefore does not increase derivation cost, allowing an attacker with an affected container, disk image, or volume header to perform substantially cheaper offline password guesses. Official precompiled VeraCrypt binaries and normal distribution packages use the standard PBKDF2 backend and are not affected. Volumes created by an affected WOLFCRYPT=1 build require backup and recreation because corrected builds derive different keys. This issue is fixed in version 1.26.29.

VeraCrypt provides disk encryption with strong security based on TrueCrypt. From 1.26.6 until 1.26.29, file-hosted hidden volume creation forces quick format and the FormatNoFs function in src/Common/Format.c and FormatFat function in src/Common/Fat.c use WriteFile to place raw zeroed sectors at predictable 128 MiB intervals. These writes bypass the normal EncryptDataUnits formatting path, leaving deterministic plaintext markers in an area expected to resemble random ciphertext. The markers can weaken plausible deniability during forensic inspection, although they do not disclose hidden-volume content or reduce the strength of VeraCrypt encryption. This issue is fixed in version 1.26.29.